Exchange 2010 SP1 - ErrorRecord: Database is mandatory on UserMailbox error

We planned to upgrade our Exchange 2010 servers to SP1 this labor day weekend to take advantage of these calendar-related improvements:

• Outlook Web App Improvements
• Calendar Repair Assistant supports more scenarios than were available in Exchange 2010 RTM.
• Mailbox Assistants are now all throttle-based (changed from time-based in Exchange 2010 RTM).
• Internet calendar publishing allows users in your Exchange organization to share their Outlook calendars with a broad Internet audience.
• Importing and exporting .pst files now uses the Mailbox Replication service and doesn't require Outlook.

(fyi be prepared to install hotfixes before installing SP1!)

But what happens when it fails on the mailbox role with these two errors?

1. ErrorRecord: Database is mandatory on UserMailbox. Property Name: Database



2. Microsoft.Exchange.Data.DataValidationException: Database is mandatory on UserMailbox. Property Name: Database

It seems we had to upgrade active directory (i.e, run setup.com /ps, then /p, and then /pad)

But that threw an error "Setup previously failed while performing the action "BuildToBuildUpgrade"

There are two fixes to this problem. The FIRST Fix - edit the registry (seems like that's always part of a fix), and SECOND remove a few system mailboxes:

Edit the registry. Under the key HKLM\Software\Microsoft\ExchangeServer\v14\MailboxRole you will find two keys - Watermark and Action. Export the mailbox role settings, then delete the two keys. Now re-run setup.com /ps, then /p, and then /pad. )I tried running the setup GUI, but it didn't completely upgrade AD.)

The SECOND fix: Now we're back to the initial "Database is mandatory on UserMailbox" problem. Launch AD Users & Computers, and delete the discovery mailbox, system mailbox(es)

Finally, if you are deploying Exchange 2010 for the first time, Exchange 2010 SP1 is a full install package. Pat Richard's Exchange2010Prereqs.ps1 script simplifies installation.

>>Update After I brought the servers back online and started writing this post, I found Brian Day's post in Technet (...wish I had found it earlier!)

--Russ